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Upper Bounds for the Essential Dimensionof E7

Published online by Cambridge University Press:  20 November 2018

Mark L. MacDonald*
Affiliation:
Department of Mathematics and Statistics, Fylde College, Lancaster University, Bailrigg, Lancaster LA1 4YF, United Kingdom e-mail: m.macdonald@lancaster.ac.uk
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Abstract.

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This paper gives a new upper bound for the essential dimension and the essential 2-dimension of the split simply connected group of type ${{E}_{7}}$ over a field of characteristic not 2 or 3. In particular, $\text{ed}\left( {{E}_{7}} \right)\,\le \,29$, and $\text{ed}\left( {{E}_{7}};\,2 \right)\,\le \,27$.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 2013

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